Washer with self-reversing spray arm assembly

ABSTRACT

A rotatable spray arm, for a washing machine such as a dishwasher or the like, is caused to rotate by the resultant counterforce of a washing fluid conducted through the body of the spray arm and outwardly as a jetstream from a rotatable nozzle on the end of the spray arm. The spray arm is provided with a mechanical linkage that translates motion from a nut and axial screw arrangement to the rotatable nozzle assembly at the end of the spray arm. This translating action permits the nozzle to successively swivel between first and second drive positions to thereby repeatedly reverse the direction of rotation of the spray arm. Each swivel action of the nozzle, from one of its drive positions to the other, takes place after a predetermined number of revolutions of the spray arm. Rotation of the spray arm and its repeating reversal action continues as long as a pressurized flow of washing fluid is maintained in the spray arm to provide the jetstream from the rotatable nozzle.

United States Patent Guth [54] WASHER WITH SELF-REVERSING SPRAY ARM ASSEMBLY [72] Inventor: Lauren W. Guth, Louisville, Ky.

[73] Assignee: General Electric Company [22] Filed: Dec. 29, 1969 [21] Appl. No.: 888,267

Related (1.5. Application Data [63] Continuation of Ser. No. 799,574, Feb. 17, I969,

abandoned.

[52] US. Cl ..239/255, 239/227 [51] Int. Cl ..B05b 3/06 [58] Field ofSearch ..239/251-258, 227; 134/176, 179

[56] References Cited UNITED STATES PATENTS 1,408,077 2/ 1922 Clinton ..239/255 X 1,733,249 10/1929 Clinton.. ..239/255 3,261,554 7/1966 Perl ..239/256 X Primary Examiner-M. Henson Wood, Jr.

Assistant Examiner-John J. Love Attorney-George C. Atwell, Harry F. Manbeck, J r., Frank L. Neuhauser, Oscar B. Waddell and Joseph B. For-man [57] ABSTRACT A rotatable spray arm, for a washing machine such as a dishwasher or the like, is caused to rotate by the resultant counterforce of a washing fluid conducted through the body of the spray arm and outwardly as a jetstream from a rotatable nozzle on the end of the spray arm. The spray am is provided with a mechanical linkage that translates motion from a nut and axial screw arrangement to the rotatable nozzle assembly at the end of the spray arm. This translating action pennits the nozzle to successively swivel between first and second drive positions to thereby repeatedly reverse the direction of rotation of the spray arm. Each swivel action of the nozzle, from one of its drive positions to the other, takes place after a predetermined number of revolutions of the spray arm. Rotation of the spray arm and its repeating reversal action continues as long as a pressurized flow of washing fluid is maintained in the spray ann to provide the jetstream from the rotatable nozzle.

5 Claims, 8 Drawing Figures PMENFEBFEB 15 m2 396432.208

sum 1 [1F 2 l 5 8 y M Hss ATTORNEY S INVENTOR LAUREN w. GUTH FAIENTEDFEB 15 m2 SHEET 2 OF 2 ,32 FIG-2 F'IG.4

INVENTOR. LAU REN W. GUT H Z? 5 M FIG.6

I-Hs ATTORNEY WASHER WITH SELF-REVERSING SPRAY ARM ASSEMBLY CROSS-REFERENCE TO A RELATED APPLICATION This is a continuation of an application filed on Feb. 17, I969, Ser. No. 799,574, and now abandoned.

BACKGROUND OF THE INVENTION In recent years various constructions for washing machines of the automatic dishwasher type have been introduced. Many manufacturers have adopted the design or general construction which includes a cabinet or housing defining a wash chamber having an elongated hollow casing or spray arm mounted for rotation in the chamber. The rotatable spray arm serves to distribute a washing fluid by means of a plurality of orifices in a spaced apart relation on the spray arm body. It is common to adapt the spray arm to be driven or rotated on its axis by a counter force exerted from a comparatively high velocity discharge of the washing fluid. Usually, at least one of the orifices is adapted to emit a jetstream on a line substantially perpendicular to the longitudinal axis of the spray arm. On the type of spray arm that rotates on a centrally disposed vertical axis, the orifice that is adapted to emit the jetstream that provides the counter force action is generally located toward an outer end of the spray arm.

Persons familiar with the art are aware that a more uniform and improved pattern of washing fluid distribution within the wash chamber of a dishwasher can be attained by implementing the spray arm with means to attain successive reversals of the direction of rotation of the spray arm during the washing and rinsing steps of the operational cycle. One example of apparatus designed to achieve this reversal effect is illustrated in U.S. Pat. No. 3,160,164 issued Dec. 8, 1964 to F. G. Constance et al., wherein automatic reversal of rotation of a spray arm takes place in response to changes in the fluid pressure of liquid discharged from the spray arm. The present invention, however, is believed more closely related to a copending application, Ser. No. 845,144, invented by D. S. Cushing and assigned to the assignee of the present invention. Cushing discloses an arrangement for providing a sequentially reversing action to a dishwasher spray arm that operates automatically once the washing machine is placed into operation. The present invention is a new improved system for providing an automatically reversing spray arm of the reaction-driven type as broadly presented by Cushing.

Among a number of advantages of the present invention that will become apparent in the ensuing detailed description is its comparatively low production cost and its relatively long adjustment-free operating life.

SUMMARY OF THE INVENTION The invention may be broadly summarized as a selfreversing spray arm assembly for an automatic dishwasher or the like having mechanical linkage means that is sensitive to the rotating motion of the spray arm whereby the mechanical linkage means is automatically actuated to allow a jetdischarge nozzle to successively reverse position on the spray arm and thus cause the spray arm to reverse its direction of rotation on its axis.

In the presently preferred embodiment of the invention, the mechanical linkage means is contained wholly within the body of the rotatable spray arm and includes a traveling member or actuating nut that moves longitudinally during the operation of the machine, on the shaft about which the spray arm rotates. The actuating nut reverses its direction of movement relative to the shaft on which it is carried each time the direction of rotation of the spray arm is reversed. A control arm within the body of the spray arm extends from the actuating nut outwardly to the reversible discharge nozzle located toward one end of the spray arm. The control arm causes the longitudinal movement of the actuating nut on the stationary shaft to be translated in a reciprocating action to the outer end of the control arm where, after a predetermined number of revolutions of the spray arm, release means is thereby actu- Mai ated to permit the rotatable nozzle to swivel in response to the counter force exerted by its own jetstream. The rotatable nozzle then swivels between its operating positions and thereby effects the reversal of the direction of rotation of the spray arm on which it is carried. The reversal action of the spray arm continues sequentially so long as a pressurized flow of the washing fluid is being pumped therethrough.

An important feature in the construction of the invention is the incorporation of a slip-clutch arrangement as a means of connecting the inner end of the control arm to the actuating nut carried on the stationary shaft about which the spray arm turns. The actuating nut is uniquely adapted to slip in its engagement with the control arm to prevent damage to the mechanism in the event that an operator of the dishwasher should manually rotate the spray arm past the point where the spray arm assembly would normally self-reverse during actual operation of the machine. This feature prevents damage to constituent parts of the assembly while maintaining the spray arm assembly in readiness for regular use in resumption of the self-reversing action when washing fluid is again pumped through the spray arm.

DETAILED DESCRIPTION OF THE DRAWINGS A presently preferred embodiment of the invention is illustrated in the accompanying drawings, wherein:

FIG. 1 is a front elevational view of an automatic dishwasher, shown with portions thereof partially cutaway to clearly illustrate details of the internal construction of the machine: 4

FIG. 2 is a plan view of a portion of a spray arm shown in FIG. 1;

FIG. 3 is a sectional view taken substantially along lines 3 3 of FIG. 2;

FIG. 4 is a bottom plan view of the end of the spray arm shown in FIG. 1, here shown as a comparatively larger view and partially cutaway to illustrate the disposition of certain elements of the assembly when the rotatable jet nozzle thereof is in one of its operating positions;

FIG. 5 is a sectional view taken along lines 5-5 of FIG. 2 to illustrate the disposition of certain elements of the invention when the rotatable jet nozzle thereof is at the operating position shown in FIG. 4;

FIG. 6 is a plan view similar to FIG. 4, of the outer end of the spray arm but illustrating the relative positioning of certain elements of the assembly when the rotatable nozzle is in its other or opposite operating position as compared to that illustrated in F IG. 4;

FIG. 7 is a sectional view similar to FIG. 5 but showing the change in the relative positioning of the elements therein that corresponds to the position of the rotatable jet nozzle as shown in FIG. 6; and

FIG. 8 is a plan view showing the ends of a control arm of the assembly. The control arm is a part of a mechanical linkage means of the assembly and it is also shown in FIGS. 5 and 7.

DESCRIPTION OF THE PREFERRED EMBODIMENT Illustrated in FIG. 1 is an automatic dishwasher 10 having an outer housing or cabinet 11 defining a substantially large inner compartment or wash chamber 12 therein. A pair of dish-supporting racks 13 are slidably mounted within the wash chamber 12. A front closure door 14 is provided on the automatic dishwasher l0 and is hinged at its lower end whereby it may be pulled outwardly, downwardly to permit access to the wash chamber 12. With the door I4 in its open position either of the racks 13 may be withdrawn to extend partially out of the wash chamber to facilitate the loading and unloading of tableware therein.

The wash chamber 12 is defined by a sloping bottom wall or floor 15 that slopes downwardly, inwardly generally toward its center and is formed with an upwardly protruding humplike portion 16. A circular opening 17 is provided through the floor 15 adjacent the humplike portion 16. Located beneath the opening 17 and in communication therewith is a sump 19 that serves to direct accumulated washing fluid from the wash chamber downward toward a motor-pump assembly 20. The motor-pump assembly 20 is centrally disposed below the floor 15 and includes an electric motor 21, a pump 22 and an electrically operated diverter valve 23. A conduit 24 is utilized to join the sump 19 in liquid flow communication with the intake side of the pump 22. The pump 22 is provided with a laterally facing drain discharge outlet 26 that is regulated by means of the valve 23. At the end of an operational cycle of the dishwashing machine 10 washing fluid is conducted by suitable conduit means (not shown) from the discharge outlet 26 to the household sewage system.

The electrically operated valve 23 (details of its construction not shown) is a diverter type valve adapted to be timeractuated to operate between two positions whereby in one position the discharge outlet 26 disclosed an upwardly facing pump outlet 27 is open, while in the other of its operative positions the valve 23 serves to close the main outlet 27 from the pump 22 and open the discharge outlet 26. With outlet 27 open and the discharge outlet 26 closed, the motor-pump as sembly 20 is adapted to recirculate washing fluid from and back to the wash chamber 12 during the washing and rinsing steps of the dishwashers operational cycle. When the diverter valve 23 is disposed to close the outlet 27 and open the outlet 26, the washing fluid received from the conduit 24 by the pump 22 is drained from the machine through the effluent discharge outlet 26.

The apparatus thus far described with reference to FIG. 1 is fairly representative of conventional dishwasher construction and the present invention is not limited or restricted to such construction. Other conventional equipment which might be provided in the dishwasher (not shown) includes an electrically actuated liquid inlet valve for directing water into the washing chamber 12, a timer motor sequence control means for automatically directing the machine through its operational cycle by energizing and deenergizing such components as the water inlet valve, the means actuating the diverter valve 23 and the motor-pump assembly 20.

With continued reference to FIG. 1, the main pump outlet 27 communicates, by means of an opening through the humplike floor portion 16, through a collarlike centrally bored pedestal 28, to the hollow body of an elongated hollow casing or spray arm 30. The spray arm 30 is mounted for rotation about a central vertical axis, and it may be formed as shown from a lower elongated rigid troughlike spray arm portion 31 that has its peripheral edge outwardly flanged and joined to a correspondingly shaped rigid upper spray arm portion 32. The lower and upper spray arm portion 31 and 32 of the spray arm 30 define a washing fluid passageway 33 therebetween.

Each of the two spray arm portions 31 and 32 has a central circular opening therethrough, one aligned with the other, which enables the spray arm to be mounted on a central support member 34. The support member 34, as shown in FIGS. and 7, extends upwardly through the spray arm and in sealed communication therewith whereby washing fluid may be pumped upwardly through the spray arm pedestal and into the support member 34 and thence outwardly through the fluid passageway 33 in the spray arm. The support member 34 is rotatably mounted on vertically oriented stationary shaft 35. The lower end of the stationary shaft 35 is firmly anchored in a fixed support base portion (not shown) centrally disposed within the pedestal 28. The support member 34 has a central throat portion 36 through which the shaft 35 extends and is provided with upper and lower bushings 37 to permit rotation relative to the shaft 35. The lower circumferential edge of the support member 34 moves in a circular path in close proximity to the upper edge of the pedestal 28 when the support member 34 is rotated on the shaft 35.

A circumjacent sealing means may be provided between the lower edge of the support member 34 and the upper end of the Ann pedestal 28 to prevent leakage of washing fluid therebetween, however, maintaining a close tolerance between these adjacent surfaces will prevent excessive fluid leakage therebetween. Some leakage can be tolerated to the'extent that an appreciable fluid pressure drop is not caused thereby which will effect the washing action in the machine.

It will be noted that the outer cylindrical surface of the support member 34 tapers inwardly towards its upper end. A plurality of circumferentially spaced apart bosses 38 are provided at the upper end of the support member 34. Each boss 38 is internally threaded to accommodate a screw 39. The plurality of screws 39 serve to fasten a cuplike cover or dome 40 in position over the support member 34 and to hold the spray arm 30 in sealed relation to the support member 34. It will be noted also that the support member 34 has planar vertically oriented bridging portions 41 integral thereto and extending between the central throat portion 36 and the outer cylindrical side wall of the support member 34. The bridging portions 41 interconnect the central throat portion 36 with the outer cylindrical wall of the support member 34 and are disposed in a quadrant arrangement whereby interstices are defined therebetween to permit the flow of pressurized fluid through the support member 34. Openings 44 are provided in the outer sidewall of the support member 34 in alignment with the passage 33 of the spray arm 30 whereby pressurized fluid moving upwardly through the interstices between the bridging portions of 41 may flow outwardly toward the outer end of the spray arm 30.

The radially extending bridging portions 41 each tapers inwardly within the upper end of the support-member 34. Reinforcing portions 45 may be extended between adjacent pairs of the bridging portions 41 in a horizontal plane to add stability to the assembly. At the upper end of the stationary shaft 35 a nut 46 is threadably carried to contain the support member 34 in its rotatable position on the shaft 35. As shown in FIGS. 5 and 7, two of the bridging portions 41 disposed opposite to each other have portions thereof cutaway to accommodate linkage means of the assembly as will be hereafter in further detail.

With reference to FIG. 2 the upper surface or upper portion 32 of the spray arm 30 is provided with a plurality of spray orifices 47 which receive a flow of pressurized fluid through the spray arm passageway 33 and distribute it upwardly toward items stored in the dish-supporting racks 13 shown in FIG. 1. At its other end the spray arm is provided with a nozzle assembly 48that also receives a flow of pressurized fluid from the spray arm passageway 33 and directs it outwardly whereby the counterforce 0f the stream emitted therefrom tends to urge the spray arm 30 to rotate with the support member 34 about its vertical axis.

The nozzle assembly 48 includes a rotatable nozzle or discharge head 50 adapted to swivel between two operative positions on a nozzle support platform 51 disposed over a rectangular opening 52 in the spray arm portion 32. The nozzle 50 is disposed over an opening 53 in the platform 51 and has a hollow neck portion protruding through the opening 53 to receive a fluid flow from the passage 33 of the spray arm 30. The neck portion of the nozzle 50 is provided with upper and lower annular flange portions 54 for forming a rotatable connection between the nozzle 50 and the platform 51.

As shown in FIGS. 3 through 7, the linkage means or translation means for controlling the swiveling action of the nozzle 50 relative to the spray arm 30 includes an actuating rod or control arm 55, preferably formed from a semirigid plastic material, that extends from beneath the nozzle assembly 48 and through the passageway 33 to the stationary shaft 35. The inner end of the control arm 55 is connected for movement on an actuating nut or traveling member 56 that is threadably engaged on the intermediate portion of the stationary shaft 35 as shown in FIGS. 5 and 7. The inner end of the control arm 55 as shown in FIG. 8, is provided with a centrallylocated circular eye or opening 57 for receiving therethrough the intermediate portion of the actuating nut 56. FIG. 8 also shows that the extreme inner end of the control arm 55 is provided, adjacent the opening 57, with a nut-carrying platform portion 58 created by the provision of a U-shaped slot 59 and oppositely disposed transverse undersurface grooves 60. The grooves 60 extend transversely across the undersurface of the control arm on a line intersecting the two legs of the U-shaped slot 59 whereby a line taken through the aligned grooves 60 will bisect the opening 57. This arrangement permits the control arm end to be flexed or bent along the undersurface grooves 60, with the actuating nut 56 mounted thereon, on a line transverse to the vertical axis of the nuts cylindrical portion. Then, by provision of a top surface laterally extending groove 61, the end of the control arm 55 may also be flexed or bent in a direction opposite to that permitted by the groove 60. Therefore, provision of the grooves 60 and 61, the end of the control arm 55 is double hinged and may be flexed or bent from the straight or horizontal position in FIG. 5 to the configuration shown in FIG. 7 without exerting a twisting force against the actuating nut 56. Construction of the control arm 55 from a material such as high density polypropylene permits the hinge arrangement of its inner end to be easily achieved by provision of the grooved and slotted arrangement as shown in FIG. 8.

The outer end of the control arm 55 projects beneath and engages the nozzle assembly 48. It will be noted that the control arm 55 has an elongated intermediate portion that merges into a generally square-shaped outer end portion or verge 64 that underlies the nozzle 50 as shown in FIG. 3. As shown in FIGS. 4 and 6, the control arms outer end or verge 64 has a pair of identical spaced-apart surface projections or inward and outward verge teeth 65 jutting upwardly therefrom toward the bottom nozzle 50. In operation of the spray arm assembly, each verge tooth 65 serves independently as a stop block to engage a downwardly projecting nozzle tooth or shoulder 66 integral to the lower flange 54 of the nozzle throat portion.

FIG. 3 shows that the nozzle assembly 48 further includes a pair of oppositely disposed spacer blocks 66. Each spacer block 66 is an integral part of the platform 51 and is provided with a threaded hole therein which aligns with an opening through the lower spray arm portion 30 whereby a screw 67 can be threadably inserted to fasten the entire nozzle assembly 48 in its installed position on the spray arm 30. Each of the spacer blocks 66 is provided with a grooved area whereby the pair of spacer blocks forms a retaining guide track, in cooperation with the inside surface of the spray arm portion 30, for guiding the verge 64 of the control arm in a horizontal sliding motion during the operation of the spray arm assembly.

The position of the nozzle 50 relative to the spray arm 30, as shown in FIGS. 2 and 3, is one of the two operative positions of the nozzle 50. When the nozzle 50 is in the position shown in FIG. 2 the control arm 55 is disposed as shown in FIGS. 3, 4 and 5. It will be noted in FIG. 3 that the tooth-shaped shoulder 68 extends downwardly integral to the lower flange 54 at a point along the periphery thereof. A fluid flow through the spray arm 30 and outwardly through the nozzle 50 tends to urge the nozzle 50 to swivel in a counterclockwise direction as viewed in FIG. 2, but the swiveling action 68 (FIGS. 3 and 4) is prevented because the shoulder impinges against the inward verge tooth 65 and prevents the nozzle from turning relative to the platform 51. Therefore, the counterforce of the stream emitted from the nozzle 50 is translated through the nozzle 50 to the spray arm 30 and causes the spray arm to rotate in a counterclockwise direction.

As shown in FIG. 5, when the spray arm 30 rotates about the stationary shaft 35, the actuating nut 56 carried in the opening 57 of the control arm 55 is caused to advance upwardly by means of its threaded engagement to the shaft 35. In the presently preferred embodiment of the spray arm assembly, when the spray arm 30 has rotated in a counterclockwise direction for approximately revolutions the vertical advancement of the actuating nut 56 will have imparted a horizontal sliding action to the outer end of the control arm 55 whereby the outer end portion or verge 64 thereof will have been moved from the position shown in FIG. 4 to that shown in FIG. 6. This movement of the verge 64 serves to move the verge teeth 65 toward the center of the spray arm and moves the inward verge tooth 65 out of its engagement with the nozzle shoulder 68 whereby the nozzle 50 is released to swivel to the other of its operating positions as indicated by the dotted outline of the nozzle 50in FIG. 6. The horizontal movement of the verge 64, that occurs as previously described when the actuating nut 56 moves upwardly on the stationary shaft 35, also serves to move the second or outward verge tooth 65 into the circular path of movement of the nozzle shoulder 68. The shoulder 68, when the nozzle 50 swivels on its platform 51, impinges against the second verge tooth 65 (FIG. 6) after the nozzle 50 has swiveled from the position shown in FIG. 2. The direction of the fluid stream emitted from the nozzle 50 is thereby reversed relative to the spray arm 30, thereby reversing the direction of the counterforce imparted to the spray arm by the stream emitted from the nozzle 50. By this arrangement the counterclockwise rotation of the spray arm 30 is slowed and finally halted and then reversed so that the spray arm rotates in a clockwise direction as view in FIG. 2.

When the clockwise rotation (FIG. 2) of the spray arm begins, the actuating nut 56 is disposed at an uppermost position as shown in FIG. 7. Continued rotation of the spray arm has the effect of moving the actuating nut 56 downward on the shaft 35. Downward movement of the actuating nut 56 from the position in FIG. 7 is translated through the control arm 55 whereupon the verge 64 thereof is gradually moved outwardly toward the outer end of the spray arm from the position shown in FIG. 6 to that shown in FIG. 4. Such movement of the verge 64 causes the engaged tooth 65 to move out of the circular path of the shoulder 68 and thereby again permit the nozzle 50 to swivel in reaction to the fluid stream being discharged therefrom. The nozzle 50 is then free to swivel, in a counterclockwise direction as viewed in FIG. 2, back toward its first operating position where it is halted when its downwardly projecting shoulder 68 engages the inward verge tooth 65 which has been moved back into the shoulders circular path movement.

It will be noted that the withdrawal action of the verge 64 in response to movement of the actuating nut 56 serves to move one of the verge teeth 65 out of the circular path of movement of the nozzle shoulder 68 while simultaneously moving the other verge tooth 65 into the shoulders path of movement at a point diametrically opposite to the point vacated by the first mentioned verge tooth. Thus, reciprocal movement of the verge 64 in response to the upward and downward movement of the actuating nut 56 on the shaft 35 serves to free the nozzle 50 so that it is continually advanced 180 relative to its immediately previous operating position. Each successive 180 rotation of the nozzle 50 on the spray arm 30 imparts a braking action to the rotating spray arm and reverses the direction of rotation of the spray arm. The successive reversal operation of this spray arm assembly heretofore described will continue, with the spray arm 30 repeatedly reversing its direction of rotation in response to the swiveling action of the nozzle 50, until the flow of washing fluid through the spray arm 30 is interrupted.

Referring now to FIG. 5, the means in which the actuating nut 56 is attached to the inner control arm end is considered an important aspect of the invention. The actuating nut 56 is specifically adapted to be so firmly fixed to the control arm end as to substantially avoid lateral movement between the two parts. This assures that upward and downward movement of the inner end of the control arm 55 will be translated as an immediate positive action in the outer end or verge 64. However, the actuating nut 56 is nevertheless adaptively fitted to the inner end of the control arm 55 so as to slip into its engagement therewith under a condition of comparatively high torque application. The result obtained is that during a normal operation of the spray arm assembly, the actuating nut 56 in the control arm 55 on which it is mounted will rotate in unison about the stationary shaft 35. Then, should the spray arm 30 be manually rotated by the operator of the dishwasher at a time when the actuating nut is at the extreme end of its path of movement, either at its uppermost position shown in FIG. 7 or its lowermost position shown in FIG. 5, the actuating nut 56 will cease to move with respect to the shaft 35 and thereupon slide in its engagement with the inner end of the control arm 55. By this arrangement, a slip-clutch means is provided for protecting the mechanism and maintaining the spray arm assembly in readiness for immediate use.

it should also be noted, with reference to FIG. 8, that the inner end of the control arm 55 may be provided with a guide slot 69. One of the bridging portions 41, as shown in FIGS. and 7, may be suitably cutaway adjacent the throat portion of the support member 34 to provide a vertical track edge 70 to cooperatively engage the slot 69. The bridging portion 41 opposite to the one provided with the guide track 70 may also be suitably cutaway to leave a narrow outer edge portion 71, as shown in FIGS. 5 and 7, on which the inner surface of a groove 72 (FIG. 8) in the rod 55 may bear when the rod 55 moves inwardly and outwardly relative to the spray arm 30 during operation of the assembly. Provision of the slot 69 and the slot 72 in the inner end of the control arm 55, although not necessary for the operation of the assembly, tends to prevent a twisting or lateral bending of the control rod 55 due to the torque applied thereagainst each time the rotation of the spray arm 30 reverses.

It should now be apparent from the preceding description that the present invention provides a new and improved spray arm assembly for a washing machine having means to effect automatic successive reversal of rotation of the spray arm to thereby provide a greatly improved pattern of washing fluid distribution within the washing chamber of the machine.

The preceding description and the various FIGURES of the drawing pertain only to an illustrative embodiment of the invention. It is intended that the appended claims define the subject matter of the invention and it is specifically not intended that the invention be limited to the particular details of construction in the example presented. Although the invention has been described with a certain degree of particularity, it is understood that numerous changes or modifications in the details of the construction and the combination or arrangement of parts may be resorted to without departing from the true spirit and scope of the invention as set forth in the appended claims.

The invention is distinctly pointed out and particularly claimed as:

l. A reversing spray arm assembly comprising:

a. a rotatable spray arm adapted to receive a pressurized liquid,

b. said arm having fluid discharge means for rotating said spray arm from the resultant counterforce of fluid discharge flow therefrom,

c. said fluid discharge means being adapted to move in relation to said spray arm to permit change in the direction of the fluid flow discharge therefrom and thereby reverse the direction of said spray arm,

d. translation means actuated by rotation of said spray arm responsive to change in direction of rotation of said spray arm, including a fixed shaft on which said spray arm is rotated and an intermediate threaded portion on said shaft,

e. an internally threaded sliding member carried on said intermediate threaded portion for coaxial movement along said shaft,

f. said fluid discharge means being adapted for rotation between first and second operative positions to thereby cause the direction of said spray arm to reverse, and

g. said fluid discharge means being further adapted to be released by movement of said translation means whereby said fluid discharge means is free to rotate away from the one of its operative positions where it is disposed at the time of its release. 2. The combination of claim 1 wherein said fluid discharge means includes a nozzle rotatable on an axis substantially parallel to the axis of rotation of said spray arm.

3. A reversing spray arm assembly comprising:

a. a rotatable spray arm adapted to receive a pressurized liquid, I

b. said arm having fluid discharge means for rotating said spray arm from the resultant counterforce of fluid discharge flow therefrom,

c. said fluid discharge means being adapted to move in relation'to said spray arm to permit change in direction of the fluid flow discharge therefrom and thereby reverse the direction of said spray arm,

d. translation means actuated by rotation of said spray arm and responsive to change of direction of rotation of said spray arm,

e. said translation means including an elongated control rod extending from the axis of said spray arm and through a portion of said spray arm to said fluid discharge means,

f. said fluid discharge means being adapted for rotation between first and second operative positions to thereby cause the direction of said spray arm to reverse, and said fluid discharge means being further adapted to be released by movement of said translation means whereby said fluid discharge means is free to rotate away from the one of its operative positions where it is disposed at the time of its release.

4. The combination of claim 1 wherein said riding member is adapted to slip, relative to said intermediate threaded portion, when it reaches the end of its coaxial movement thereon.

5. The combination of claim 3 wherein said elongated rod is formed from a semirigid composition and has a hinge portion along its length whereby it may bend during the operation of the spray arm assembly. 

1. A reversing spray arm assembly comprising: a. a rotatable spray arm adapted to receive a pressurized liquid, b. said arm having fluid discharge means for rotating said spray arm from the resultant counterforce of fluid discharge flow therefrom, c. said fluid discharge means being adapted to move in relation to said spray arm to permit change in the direction of the fluid flow discharge therefrom and thereby reverse the direction of said spray arm, d. translation means actuated by rotation of said spray arm responsive to change in direction of rotation of said spray arm, including a fixed shaft on which said spray arm is rotated and an intermediate threaded portion on said shaft, e. an internally threaded sliding member carried on said intermediate threaded portion for coaxial movement along said shaft, f. said fluid discharge means being adapted for rotation between first and second operative positions to thereby cause the direction of said spray arm to reverse, and g. said fluid discharge means being further adapted to be released by movement of said translation means whereby said fluid discharge means is free to rotate away from the one of its operative positions where it is disposed at the time of its release.
 2. The combination of claim 1 wherein said fluid discharge means includes a nozzle rotatable on an axis substantially parallel to the axis of rotation of said spray arm.
 3. A reversing spray arm assembly comprising: a. a rotatable spray arm adapted to receive a pressurized liquid, b. said arm having fluid discharge means for rotating said spray arm from the resultant counterforce of fluid discharge flow therefrom, c. said fluid discharge means being adapted to move in relation to said spray arm to permit change in direction of the fluid flow discharge therefrom and thereby reverse the direction of said spray arm, d. translation means actuated by rotation of said spray arm and responsive to change of direction of rotation of said spray arm, e. said translation means including an elongated control rod extending from the axis of said spray arm and through a portion of said spray arm to said fluid discharge means, f. said fluid discharge means being adapted for rotation between first and second operative positions to thereby cause the direction of said spray arm to reverse, and g. said fluid discharge means being further adapted to be released by movement of said translation means whereby said fluid discharge means is free to rotate away from the one of its operative positions where it is disposed at the time of its release.
 4. The combination of claim 1 Wherein said riding member is adapted to slip, relative to said intermediate threaded portion, when it reaches the end of its coaxial movement thereon.
 5. The combination of claim 3 wherein said elongated rod is formed from a semirigid composition and has a hinge portion along its length whereby it may bend during the operation of the spray arm assembly. 